Characterisation of Plant Growth-Promoting Endophytic Bacteria from Sugarcane and Their Antagonistic Activity against Fusarium moniliforme

The use of endophytic bacteria in agriculture provides an effective way of improving crop yield and significantly reducing chemical usage, such as fungicides. This research was conducted to explore endophytic bacteria with plant growth promotion (PGP) and antifungal activities against Fusarium moniliforme AIT01. In this study, we obtained 52 isolates of endophytic bacteria associated with the roots and stems of sugarcane from Nakhon Ratchasima province, Thailand. In vitro antagonistic activity test showed that 14 out of 52 isolates had antagonistic activity against the fungal pathogen F. moniliforme AIT01. These antagonistic endophytic bacteria were identified as belonging to six different species as follows: Nguyenibacter vanlangensis, Acidomonas methanolica, Asaia bogorensis, Tanticharoenia aidae, Burkholderia gladioli and Bacillus altitudinis based on phenotypic characteristics, along with phylogenetic analysis of their 16S rRNA gene sequences. Seven isolates effectively inhibited F. moniliforme AIT01 mycelial growth by up to 40%. The volatile compounds of six isolates reduced the growth of F. moniliforme AIT01 by over 23%. Moreover, riceberry rice seedlings previously treated with B. gladioli CP28 were found to strongly reduce infection with phytopathogen by 80% in comparison to the non-treated control. Furthermore, the isolates also showed relevant PGP features, including ammonia production, zinc and phosphate solubilisation, auxin and siderophore biosynthesis. These results demonstrated that the tested endophytic bacteria could be successfully utilised as a source of PGP and biocontrol agent to manage diseases caused by F. moniliforme.

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Effect of the endophytic plant growth promoting Enterobacter ludwigii EB4B on tomato growth

Hellenic Plant Protection Journal ◽

10.2478/hppj-2020-0006 ◽

2020 ◽

Vol 13 (2) ◽

pp. 54-65 ◽

Cited By ~ 1

Author(s):

M.E.A. Bendaha ◽

H.A. Belaouni

Keyword(s):

Root Length ◽

Biocontrol Agent ◽

Growth Promotion ◽

Dry Weight ◽

Antagonistic Activity ◽

Rrna Gene ◽

Plant Growth Promoting ◽

Enterobacter Ludwigii ◽

Tomato Growth

SummaryThis study aims to develop a biocontrol agent against Fusarium oxysporum f.sp. radicis-lycopersici (FORL) in tomato. For this, a set of 23 bacterial endophytic isolates has been screened for their ability to inhibit in vitro the growth of FORL using the dual plate assay. Three isolates with the most sound antagonistic activity to FORL have been qualitatively screened for siderophore production, phosphates solubilization and indolic acetic acid (IAA) synthesis as growth promotion traits. Antagonistic values of the three candidates against FORL were respectively: 51.51 % (EB4B), 51.18 % (EB22K) and 41.40 % (EB2A). Based on 16S rRNA gene sequence analysis, the isolates EB4B and EB22K were closely related to Enterobacter ludwigii EN-119, while the strain EB2A has been assigned to Leclercia adecarboxylata NBRC 102595. The promotion of tomato growth has been assessed in vitro using the strains EB2A, EB4B and EB22K in presence of the phytopathogen FORL. The treatments with the selected isolates increased significantly the root length and dry weight. Best results were observed in isolate EB4B in terms of growth promotion in the absence of FORL, improving 326.60 % of the root length and 142.70 % of plant dry weight if compared with untreated controls. In the presence of FORL, the strain EB4B improved both root length (180.81 %) and plant dry weight (202.15 %). These results encourage further characterization of the observed beneficial effect of Enterobacter sp. EB4B for a possible use as biofertilizer and biocontrol agent against FORL.

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Bacteria Isolated from Wastewater Irrigated Agricultural Soils Adapt to Heavy Metal Toxicity While Maintaining Their Plant Growth Promoting Traits

Sustainability ◽

10.3390/su13147792 ◽

2021 ◽

Vol 13 (14) ◽

pp. 7792

Author(s):

Abdul Wahab Ajmal ◽

Saleha Saroosh ◽

Shah Mulk ◽

Muhammad Nadeem Hassan ◽

Humaira Yasmin ◽

...

Keyword(s):

Plant Growth ◽

Agricultural Soils ◽

Culture Media ◽

Growth Promotion ◽

Metal Resistance ◽

Rrna Gene ◽

Gene Sequence Analysis ◽

Plant Growth Promoting ◽

Growth Promoting

The present study explored the plant growth promotion and bioremediation potential of bacteria inhabiting wastewater irrigated agricultural soils. Thirty out of 75 bacterial isolates (40%), 29/75 (39%) and 28/75 (37%) solubilized Zn, K and PO4 during plate essays respectively. Fifty-six percent of the isolates produced siderophores, while 30% released protease in vitro. Seventy-four percent of bacteria resisted Pb, Ni and Cd at various concentrations added to the culture media plates. Sixteen out of 75 (26%) isolates were able to fix N in Nbf medium. Among these 16 N fixers, N fixing nifH, nifD and nifK genes was detected through PCR in 8, 7 and 1 strain respectively using gene specific primers designed in the study with Enterobacter sp. having all three (nifHKD) genes. Isolated bacteria showed resemblance to diverse genera such as Bacillus, Pseudomonas, Enterobacter, Citrobacter, Acinetobacter, Serratia, Klebsiella and Enterococcus based on 16S rRNA gene sequence analysis. In addition to showing the best mineral solubilization and metal resistance potential, Citrobacter sp. and Enterobacter sp. also removed 87%, 79% and 43% and 86%, 78% and 51% of Ni, Cd and Pb, respectively, from aqueous solution. These potent bacteria may be exploited both for bioremediation and biofertilization of wastewater irrigated soils leading to sustainable agriculture.

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Genomic and Metabolomic Insights into Secondary Metabolites of the Novel Bacillus halotolerans Hil4, an Endophyte with Promising Antagonistic Activity against Gray Mold and Plant Growth Promoting Potential

Microorganisms ◽

10.3390/microorganisms9122508 ◽

2021 ◽

Vol 9 (12) ◽

pp. 2508

Author(s):

Eirini-Evangelia Thomloudi ◽

Polina C. Tsalgatidou ◽

Eirini Baira ◽

Konstantinos Papadimitriou ◽

Anastasia Venieraki ◽

...

Keyword(s):

Plant Growth ◽

Growth Promotion ◽

Gene Clusters ◽

Gray Mold ◽

Antagonistic Activity ◽

Future Research ◽

Single Culture ◽

Plant Growth Promoting ◽

Growth Promoting

The endophytic bacterial strain Hil4 was isolated from leaves of the medicinal plant Hypericum hircinum. It exhibited antifungal activity against Botrytis cinerea and a plethora of plant growth promoting traits in vitro. Whole genome sequencing revealed that it belongs to Bacillus halotolerans and possesses numerous secondary metabolite biosynthetic gene clusters and genes involved in plant growth promotion, colonization, and plant defense elicitation. The Mojavensin cluster was present in the genome, making this strain novel among plant-associated B. halotolerans strains. Extracts of secreted agar-diffusible compounds from single culture secretome extracts and dual cultures with B. cinerea were bioactive and had the same antifungal pattern on TLC plates after bioautography. UHPLC-HRMS analysis of the single culture secretome extract putatively annotated the consecutively produced antimicrobial substances and ISR elicitors. The isolate also proved efficient in minimizing the severity of gray mold post-harvest disease on table grape berries, as well as cherry tomatoes. Finally, it positively influenced the growth of Arabidopsis thaliana Col-0 and Solanum lycopersicum var. Chondrokatsari Messinias after seed biopriming in vitro. Overall, these results indicate that the B. halotolerans strain Hil4 is a promising novel plant growth promoting and biocontrol agent, and can be used in future research for the development of biostimulants and/or biological control agents.

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Identification and determination of characteristics of endophytes from rice plants and their role in biocontrol of bacterial blight caused by Xanthomonas oryzae pv. oryzae

Hellenic Plant Protection Journal ◽

10.2478/hppj-2018-0003 ◽

2018 ◽

Vol 11 (1) ◽

pp. 19-33 ◽

Cited By ~ 4

Author(s):

H. Yousefi ◽

N. Hassanzadeh ◽

K. Behboudi ◽

F. Beiki Firouzjahi

Keyword(s):

Plant Growth ◽

Endophytic Bacteria ◽

Plant Pathogens ◽

Growth Promotion ◽

Antagonistic Activity ◽

Xanthomonas Oryzae ◽

Rice Plants ◽

16S Rdna Sequence Analysis ◽

North Of Iran ◽

Plant Growth Promoting

SummaryEndophytic bacteria of rice plants (Oryza sativaL.) from eight different cultivars were screened for their ability in inducing disease symptoms, plant growth promotion and antagonistic activity againstXanthomonas oryzaepv.oryzae.Out of the 63 whole isolates, five were plant pathogens. Based on phenotypic characteristics and 16S rDNA sequence analysis, these were identified asPseudomonas oryzihabitans,P. fulva,Pantoea ananatis,Pantoeasp.,Cellulomonassp. Four out of the 63 isolates behaved as potentially good plant growth-promoting and biocontrol agents. These were identified asBacillussp.,B. subtilis,Pseudomonas putidaandEnterobactersp. This is the first report of pathogenic and endophytic bacteria from rice grown in field conditions in North of Iran.

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Isolation and characterization of plant growth promoting endophytic bacteria isolated from Vigna radiata

Indian Journal of Agricultural Research ◽

10.18805/ijare.a-5047 ◽

2018 ◽

Author(s):

Pooja Suneja ◽

Rajat Maheshwari ◽

Namita Bhutani

Keyword(s):

Plant Growth ◽

Vigna Radiata ◽

Endophytic Bacteria ◽

Fungal Pathogens ◽

Growth Promotion ◽

Restriction Analysis ◽

Isolation And Characterization ◽

Plant Growth Promoting ◽

Growth Promoting

A total of 22 endophytic bacteria were isolated from roots and nodules of Vigna radiata (mungbean) obtained from Jind district, Haryana. These were characterized on the basis of plant growth promoting traits. Almost all the endophytic bacteria produced IAA with maximum production of 81.63µg/ml by isolate MJiR8. Among these, 100% root isolates and 84.6% nodule isolates resulted in in vitro root growth promotion of mungbean seedlings. All the isolates produced ammonia; eighteen (all root and nine nodule isolates) produced organic acid while only four root isolates were positive for siderophore production. The four isolates produced hydrogen cyanide and out of these only MJiR9 inhibited the growth of fungal pathogens Fusarium oxysporium and Aspergillus niger. All the endophytes were used to determine molecular diversity by ARDRA (Amplified Ribosomal DNA Restriction Analysis) Results revealed that the nodule isolates were more diverse, being present in separate clusters, in comparison to root isolates which were grouped together in cluster III.

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Isolation of plant growth-promoting Pseudomonas sp. PPR8 from the rhizosphere of Phaseolus vulgaris L.

Archives of Biological Sciences ◽

10.2298/abs150701028k ◽

2016 ◽

Vol 68 (2) ◽

pp. 363-374 ◽

Cited By ~ 4

Author(s):

Pankaj Kumar ◽

Ramesh Dubey ◽

Dinesh Maheshwari ◽

Yong-Ha Park ◽

Vivek Bajpai

Keyword(s):

Phaseolus Vulgaris ◽

Plant Growth ◽

Growth Promotion ◽

Rrna Gene ◽

Sequencing Analysis ◽

Pseudomonas Sp ◽

Pgp Traits ◽

Plant Growth Promoting ◽

Growth Promoting

In vitro screening of plant growth-promoting (PGP) traits was carried out using eight Pseudomonas spp., PPR1 to PPR8, isolated from the rhizosphere of Phaseolus vulgaris growing on the Uttarakhand Himalayan range in India. All the isolates were fast growers, positive for catalase, oxidase and urease activities, and utilized lactose and some amino acids. All the isolates were indole acetic acid (IAA) positive, however PPR8 solubilized potassium and zinc along with various other types of inorganic (tricalcium, dicalcium and zinc phosphate) and organic (calcium phytate) phosphates, as well as producing siderophore and ACC deaminase. PPR8 also produced cyanogens, extracellular chitinase, ?-1,3-glucanase, ?-1,4-glucanase and oxalate oxidase. Based on the PGP traits of all isolates, PPR8 was found to be the most potent plant growth-promoting rhizobacteria (PGPR). Further, PPR8 was identified as Pseudomonas sp. PPR8, based on 16S rRNA gene sequencing analysis. Moreover, the PGP activities of PPR8 confirmed it to be a potent biocontrol agent, inhibiting the growth of various plant pathogenic fungi. This study reveals the potential of Pseudomonas sp. PPR8 to be used as a good bioinoculant for growth promotion of common bean and for the protection of important legume crops from various deleterious phytopathogens.

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Endophytic Bacterial Isolates From Halophytes Demonstrate Phytopathogen Biocontrol and Plant Growth Promotion Under High Salinity

Frontiers in Microbiology ◽

10.3389/fmicb.2021.681567 ◽

2021 ◽

Vol 12 ◽

Author(s):

Christos A. Christakis ◽

Georgia Daskalogiannis ◽

Anastasia Chatzaki ◽

Emmanouil A. Markakis ◽

Glykeria Mermigka ◽

...

Keyword(s):

Plant Growth ◽

Plant Growth Promotion ◽

High Salinity ◽

Growth Promotion ◽

Antagonistic Activity ◽

Rrna Gene ◽

In Planta ◽

Promoting Effect ◽

Cakile Maritima

Halophytic endophytes potentially contribute to the host’s adaptation to adverse environments, improving its tolerance against various biotic and abiotic stresses. Here, we identified the culturable endophytic bacteria of three crop wild relative (CWR) halophytes: Cakile maritima, Matthiola tricuspidata, and Crithmum maritimum. In the present study, the potential of these isolates to improve crop adaptations to various stresses was investigated, using both in vitro and in-planta approaches. Endophytic isolates were identified by their 16S rRNA gene sequence and evaluated for their ability to: grow in vitro in high levels of NaCl; inhibit the growth of the economically important phytopathogens Verticillium dahliae, Ralstonia solanacearum, and Clavibacter michiganensis and the human pathogen Aspergillus fumigatus; provide salt tolerance in-planta; and provide growth promoting effect in-planta. Genomes of selected isolates were sequenced. In total, 115 endophytic isolates were identified. At least 16 isolates demonstrated growth under increased salinity, plant growth promotion and phytopathogen antagonistic activity. Three showed in-planta suppression of Verticillium growth. Furthermore, representatives of three novel species were identified: two Pseudomonas species and one Arthrobacter. This study provides proof-of-concept that the endophytes from CWR halophytes can be used as “bio-inoculants,” for the enhancement of growth and stress tolerance in crops, including the high-salinity stress.

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A prospectus of plant growth promoting endophytic bacterium from orchid (Vanda cristata)

BMC Biotechnology ◽

10.1186/s12896-021-00676-9 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Sujit Shah ◽

Krishna Chand ◽

Bhagwan Rekadwad ◽

Yogesh S. Shouche ◽

Jyotsna Sharma ◽

...

Keyword(s):

Plant Growth ◽

Root Colonization ◽

Endophytic Bacterium ◽

Epifluorescence Microscopy ◽

In Vitro Cultivation ◽

Rrna Gene ◽

Bacillus Spp ◽

Plant Growth Promoting ◽

Growth Promoting

Abstract Background A plant growth-promoting endophytic bacterium PVL1 isolated from the leaf of Vanda cristata has the ability to colonize with roots of plants and protect the plant. PVL1 was isolated using laboratory synthetic media. 16S rRNA gene sequencing method has been employed for identification before and after root colonization ability. Results Original isolated and remunerated strain from colonized roots were identified as Bacillus spp. as per EzBiocloud database. The presence of bacteria in the root section of the plantlet was confirmed through Epifluorescence microscopy of colonized roots. The in-vitro plantlet colonized by PVL1 as well as DLMB attained higher growth than the control. PVL1 capable of producing plant beneficial phytohormone under in vitro cultivation. HPLC and GC-MS analysis suggest that colonized plants contain Indole Acetic Acid (IAA). The methanol extract of Bacillus spp., contains 0.015 μg in 1 μl concentration of IAA. PVL1 has the ability to produce antimicrobial compounds such as ethyl iso-allocholate, which exhibits immune restoring property. One-way ANOVA shows that results were statistically significant at P ≤ 0.05 level. Conclusions Hence, it has been concluded that Bacillus spp. PVL1 can promote plant growth through secretion of IAA during root colonization and ethyl iso-allocholate to protect plants from foreign infections. Thus, this study supports to support Koch’s postulates of bacteria establishment.

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Assessing the Plant Growth-promoting Traits and Host Specificity of Endophytic Bacteria of Pulse Crops

Legume Research - An International Journal ◽

10.18805/lr-4491 ◽

2021 ◽

Author(s):

R. Thamizh Vendan ◽

D. Balachandar

Keyword(s):

Plant Growth ◽

Endophytic Bacteria ◽

Gene Sequencing ◽

16S Rrna Gene Sequencing ◽

Growth And Yield ◽

Rrna Gene ◽

Plant Growth Promoting ◽

Growth Promoting ◽

Rrna Gene Sequencing ◽

Plant Growth Promoting Traits

Background: Symbiotic associations between legumes and Rhizobia are ancient and fundamental. However, the plant growth-promoting endophytes other than Rhizobia are not yet fully explored for pulses productivity. The present study was aimed to isolate efficient endophytic bacteria from pulses, assess their diversity, screen their plant growth-promoting activities and to test their potential as bio inoculants for pulses.Methods: We have isolated several endophytic bacteria from pulse crops more specifically from blackgram (Vigna mungo) and greengram (Vigna radiata). After careful screening, 15 promising endophytic isolates were selected for this study. The identification of endophytic bacterial isolates was performed by 16S rRNA gene sequencing. The isolates were tested for their potential for the plant growth-promoting traits such as nitrogen fixation, phosphate solubilization, indole-3-acetic acid production, siderophore secretion and antifungal activity. Pot culture experiments were conducted with the screened potential endophytic cultures.Result: The 16S rRNA gene sequencing revealed that species of Enterobacter, Bacillus, Pantoea, Pseudomonas, Acromobacter, Ocrobacterium were found as endophytes in blackgram and greengram. The in vitro screening identified Bacillus pumilus (BG-E6), Pseudomonas fluorescens (BG-E5) and Bacillus licheniformis (BG-E3) from blackgram and Pseudomonas chlororaphis (GG-E2) and Bacillus thuringiensis (GG-E7) from greengram as potential plant growth-promoting endophytes. These strains showed antagonism against plant pathogenic fungi. Upon inoculation of these endophytic PGPR strains, the blackgram and greengram growth and yield got increased. Among the strains, BG-E6 recorded 14.7% increased yield in blackgram and GG-E2 accounted for a 19.5% yield increase in greengram compared to respective uninoculated control. The experimental results showed that there was a host specificity found among the endophytic bacterial cultures with pulses. The cross inoculation of endophytic strains did not perform well to enhance the growth and yield of their alternate hosts.

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Plant Growth Promotion Potential Is Equally Represented in Diverse Grapevine Root-Associated Bacterial Communities from Different Biopedoclimatic Environments

BioMed Research International ◽

10.1155/2013/491091 ◽

2013 ◽

Vol 2013 ◽

pp. 1-17 ◽

Cited By ~ 27

Author(s):

Ramona Marasco ◽

Eleonora Rolli ◽

Marco Fusi ◽

Ameur Cherif ◽

Ayman Abou-Hadid ◽

...

Keyword(s):

Environmental Factors ◽

Plant Growth ◽

Bacterial Communities ◽

Growth Promotion ◽

Rrna Gene ◽

Similar Distribution ◽

Bacterial Assemblage ◽

Pgp Traits ◽

Associated Bacteria

Plant-associated bacteria provide important services to host plants. Environmental factors such as cultivar type and pedoclimatic conditions contribute to shape their diversity. However, whether these environmental factors may influence the plant growth promoting (PGP) potential of the root-associated bacteria is not widely understood. To address this issue, the diversity and PGP potential of the bacterial assemblage associated with the grapevine root system of different cultivars in three Mediterranean environments along a macrotransect identifying an aridity gradient were assessed by culture-dependent and independent approaches. According to 16S rRNA gene PCR-DGGE, the structure of endosphere and rhizosphere bacterial communities was highly diverse (P=0.03) and was associated with a cultivar/latitudinal/climatic effect. Despite being diverse, the bacterial communities associated with Egyptian grapevines shared a higher similarity with the Tunisian grapevines than those cultivated in North Italy. A similar distribution, according to the cultivar/latitude/aridity gradients, was observed for the cultivable bacteria. Many isolates (23%) presentedin vitromultiple stress resistance capabilities and PGP activities, the most frequent being auxin synthesis (82%), insoluble phosphate solubilisation (61%), and ammonia production (70%). The comparable numbers and types of potential PGP traits among the three different environmental settings indicate a strong functional homeostasis of beneficial bacteria associated with grape root.

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